1. Field of the Invention
The present invention is directed to a connection element for the electrical connection of electrical elements arranged in a group.
2. Description of the Related Art
Solutions using free wiring are generally known in the art for effecting an electrical connection of electrical elements arranged in a group. In free wiring, individual leads are guided, proceeding from a control unit generating control signals, e.g. a stored-programmable controller (SPS), to the individual electrical elements such as relays, incandescent lamps, sensors or electromagnets of valves which are arranged in groups. For protection against external influences, the leads can be brought together in a cable tree or cable harness. However, free wiring must always be carried out by hand and, in this respect, is encumbered by highly complicated assembly. In addition, the indefiniteness of free wiring makes a flawless assembly more difficult.
A solution is disclosed in German Patent 40 20 791 for simple cabling of electromagnets in valve units to avoid the disadvantages associated with free wiring. A valve unit comprises a quantity of valves grouped in a row. Each valve is controlled by an electromagnet serving as an actuator. In order to supply the individual electromagnets with a binary control signal in the low-voltage range, the electrical leads required for this purpose are accommodated in a protected manner inside a cable duct that runs along the valve unit and is modularly constructed. A common lead is shared among all of the electromagnets and is guided to one connection terminal of the electromagnets. Accordingly, only one signal line needs to be guided to the respective other connection terminal of each of the electromagnets. Since not every electromagnet is wired with a separate pair of leads in this case, the required quantity of signal lines is substantially reduced. Nevertheless, due to the use of individual wires, this solution still requires manual wiring.
German Patent No. 39 43 752 discloses a printed circuit board arrangement with plug-in connectors for the electrical connection of electromagnets in valve units, which avoids manual wiring and further reduces assembly effort. In this reference, printed circuit boards are integrated in connection blocks having pressure-medium ducts such that when a plurality of connection blocks are plugged together, in addition to a connection of the pressure-medium ducts, the electrical connection is also carried out automatically by means of plug connectors that are arranged at the sides of every printed circuit board. For protection against external influences, the printed circuit boards are accommodated within the connection block in a through-channel. While the complexity of assembly may conceivably be reduced in this solution as compared with free wiring due to use of the principle of an electric plug connection, the protective accommodation of the printed circuit boards inside the connection block which serves as a housing results in a highly complex manufacture of the connection blocks.
Therefore, it is the object of the present invention to provide a device for the electrical connection of electrical elements arranged in a group which enables relative simplicity of assembly on the one hand and can also be economically manufactured on the other hand.